Cushioned trolley pole head



Aug. 39, 194?. E. A. LARSSON CUSHIONED TROLLEY POLE HEAD Filed April 2, 1945 MU/W m m 3 Gttomeg Patented Aug. 19, 1947 CUSHIONED TROLLEY POLE HEAD Ernst A. Larsson, Mansfield, Ohio, assignor to The Ohio Brass Company, Mansfield, Ohio, a corporation of New Jersey Application April 2, 1945, Serial No. 586,160

1 Claim. 1

My invention relates to current collector heads and trolley pole harps for use therewith.

Current collectors mounted on vehicles traveling at high speeds will produce vibrations which originate at the trolley wire. These vibrations and various noises are transmitted through the trolley heads, metal poles, trolley pole bases to the car body.

The car roof upon which the trolley base is mounted acts as a sounding board and thereby accentuates the noises and transposes the vibration into sound waves, all of which is very annoying and discomforting to the passengers.

Devices have been made to check the noises and vibrations before they reach the car roof and one such device is now on the market which substantially eliminates such noise effects but is quite expensive and the amount "of vibrationabsorbing material used is considerable and at the present time is quite restricted, as in this device rubber is employed.

My invention will prevent to a certain extent these vibrations and noises passing from the h'arp to the pole suificiently for use on vehicles operating on car tracks as in the case of street cars, but not sufficiently in the case of the trolley coach operating on rubber tires, and I accomplish this result by making the harp in two parts and applying a resilient vibration and noise absorbing or deadening material where the two parts of the harp are mechanically connected.

One other important object of my invention, other than checking the flow of noise and vibration, is to permit a limited amount of relative movement of the parts of the harp in a vertical longitudinal plane. This limited vertical movement compensates for slight unevenness in the,

path of the current collector and reduces shock to the shoe which is of special advantage when carbon inserts are employed as the shoe moves along the trolley wire and tends to maintain the contact between the collector and the wire.

My invention resides in the new and useful construction, combination and relation of the parts hereinafter described. and shown in the accompanying drawing and is a continuation in part of my Patent No. 2,385,582 dated September 25, 1945, filed December 13, 1943.

In the drawing:

Fig. 1 is a top view of my invention.

Fig. 2 is a side view of Fig. 1 and shows in combination therewith a trolley pole mounting.

Fig. 3 is a view in substantially full section of my invention taken on the line 3--3 of Fig. 1.

Fig. 4 is a artial transverse section taken on the line 4-4 of Fig. 2 using a modified form of vibration absorbing hinge.

Fig. 5 is a side view in partial section of a modified vibration controlling element employed between the parts of the harp.

Fig. 6 is an end view of Fig. 5.

In the preferred embodiment of my invention I provide a harp having an upper portion I and a lower portion 2.

The upper end of portion I has spaced side arms 3 between which is mounted, to oscillate, a current collector hoe 4 or a trolley wheel may be mounted therebetween in the manner shown in the prior art. The mounting of the collector shoe 4 shown is quite similar to that disclosed in my Patent 1,890,946 of December 13, 1932.

The side arms 3 of the portion I are held in fixed and spaced relation by the cross members 5 andli which are cast integral with the side arms.

The lower end of the upper portion l is formed with two short and spaced arms 1 forming a clevis 8.

The lower portion 2 is provided with a socket 9 at its lower end to receive a pole or other support I0 while the upper end of portion 2 is formed into a tongue-like member I I which fits in the space 8 between the arms I.

The tongue portion II has a through bore I2 to receive the vibration controlling element I3 shown in Figs. 3 and 4.

This element I3 comprises three essential parts, viz., an outer metal sleeve M, an inner metal sleeve l5 and an interposed resilient or elastic member Hi.

This member I6 is composed preferably of rubber of the required yielding properties and which is positioned between the adjacent surfaces of the sleeves I4 and I5 but not secured thereto, hence the parts l4, l5 and It may oscillate relative to each other. This provides a resilient joint element I3 in which the resilient portion IE will be subject to compressive forces applied thereto as a result of the upward pressure of the trolley pole against harp and the shoe against the trolley wire as more fully explained later on.

The sleeve element I4 is provided with an outer diameter corresponding to the inner diameter of the bore I2 requiring the element I3 to be pressed into position thereby preventing relative movement of the sleeve member I4 and of the portion 2. e

The clevis arms I at the lower end of the upper portion I are bored out to a diameter corresponding to the inner diameter of the sleeve I5 3 and which diameters correspond to the outer diameter of an auxiliary sleeve I! which is a press fit with the aforesaid diameters thereby preventing any relative movement of the upper portion I and the sleeve I5.

The construction of element I3 and its attachment to the portions I and 2 are such that a relative movement of the upper and lower portions I and 2 is permitted about the axis of the sleeve II which may be termed an oscillatory movement.

The upper portion I of the harp has a projecting part I which is an extension of the part 6 and is so positioned as to engage the part 2 of the portion 2 at F (Fig. 3) while the shoe 4 is in engagement with the overhead construction since member I6 is not secured to both parts I4 and I5. This will limit the downward movement of the portion I about the axis of the sleeve I'I relative to the portion 2, but not its upward movement about the axis of the sleeve II.

The contact F acts as a fulcrum or axis and since there is a downward force acting upon the portion I under operating conditions, the portions I and 2 will tend to move relative to each other about the axis or fulcrum F but which movement will be yieldingly resisted by the part I6 of the element I3.

However this movement places the resilient element I6 under compression and since the part I6 is a yieldable material, there will be a limited arcuate movement of the portion I relative to the portion 2 about the fulcrum F depending upon the characteristics of the part I6 and the downward force acting between the shoe 4 and the overhead construction in which case the axes of the sleeve I! and bore I2 which normally coincide will separate but remain parallel.

This movement, although not great, is sufficient to tend to maintain contact between the overhead construction and the shoe 4 as it moves along the overhead and meets slight obstructions, and the shock to which the shoe is subjected is absorbed by the resilient material of the part I6.

This operation of my present invention is different from that disclosed in my Patent 2,385,582 in which the resilient member is secured to the inner and outer sleeve I4 and I5 and the sleeves secured to the portions I and 2. In my said patent the resilient member I6 is subject to a torsional force and all oscillation of the parts is the result of the resilient part of the pintle since there is no equivalent of fulcrum F.

In Fig. 4, the resilient element I6 projects beyond the ends of the sleeves I4 and I5, thereby filling the space between the clevis arms I; in Fig. 5, the resilient element I6 projects beyond the ends of the sleeves I4 and I5 but covers the ends of the sleeves I4 and I5 as at I6 thereby preventing relative side shifting of the parts. In Fig. 1, the resilient element I6 does not project beyond the sleeves I4'and I5.

Thus the shocks to which the shoe 4' is subjected as it travels along the overhead trolley wire will be absorbed by the resilient member I6 at the same time permitting a relative movement of the portions I and 2 within the element I3 and I3.

In the construction described and shown in Fig. 1, portions I and 2 are mechanically secured to ether but poorly connected electrically as at point F therefore I provide improved means to electrically connect portions I and 2.

I provide a cable or shunt I8 of flexible cable, preferably copper, which has one end flattened and attached to the side of the upper portion I by the screws I9. The cable is then carried through the unobstructed hollow of the sleeve I! to the other side of the device, and there it is secured, as by soldering or brazing or other suitable means, to the lower portion 2 as at 20.

By this construction, the shunt I8 is located at the center of movement of the portions I and 2, that is on the neutral axis, where the relative movement is the least, therefore the bending of the shunt due to the said movements of the portions I and 2 is very slight, in fact practically nil.

The shoe 4 is not claimed specifically but comprises a holder 2| mounted on the arcuate bearing 22 for oscillation. The renewable wear portion 23 is secured in position by the bolt 24.

The material of the shock absorbing members I3 and I3 is preferably of rubber, such as carsprin-g rubber, but I find that some of the socalled synthetic or substitute products therefor may be used and also some of the so-called flexible plastics.

The resilient member I6, which bridges the space between the sleeves I4 and I5, may be secured to the attaching surface of one of the sleeves by a surface union which may be produced by-various means well-known to those versed in the art of rubber manipulation and of synthetics and plastics and whereby the elastic or resilient member I6 will oscillate with that sleeve but relative to the other sleeve and sustain any radial or compressive forces actin thereon.

The amount of resilient material used in my improved construction is very much less than that used in certain prior art devices.

I use the word pintle as a convenient term for the resilient vibration and shock absorbing element I3 and I3 comprising the parts I4, I5 and I6, as it functions to hold the portions I and 2 against separation and permits limited relative oscillation of the portions much like a hinge pintle.

It is evident, that the portions I and 2 may still oscillate relative to each other about the axis of the sleeve II without resistance from the member I6 when the sleeves are secured to the portions providing the member I6 is not secured to both sleeves or is secured to only one sleeve, or if the member I6 is secured to both sleeves I4 and I5 then both sleeves or one sleeve should be free to rotate relative to the associated portion I and/or 2.

It will also be evident that one or both of the sleeves I4, I5 may be omitted and the resilient member I6 made to fill the remaining space; also the member I6 could be secured to the tongue portion and left free to oscillate relative to the other portion,

By omitting the members I4 and I5, the space for the shock member I6 is considerably greater and when unattached to the portions I and 2 considerable economy is effected in the cost of construction.

In the various modifications described above, due to the weight of portion I and its freedom of movement relative to portion 2, the said portions are in engagement at F at all times.

Further, if the parts I4, I5 and I6 should be secured together and the sleeves secured to the portions I and 2, then the members I and 2 will be so positioned as to engage when the collector is operating along an overhead trolley system and thereby form an axis or fulcrum about which the portions will oscillate, since the memher I B will yield under pressure as described above.

Having described my invention, what I claim as new and desire to secure by Letters Patent,

In a trolley head com-prising a pair of parts, one part having means to attach it to asupport and the other part provided with acurrent collector adapted to engage a trolley wire and one part having a clevis and the other part having a tongue to interfit with the clevis and each having a transverse opening aligned axially with the other opening to form a hinge joint and resilient non-metallic means interposed between the clevis and the tongue to hold the parts against separation and so related to the parts that the parts are free to oscillate relative to one another without restraint set up by torsional stress in the said resilient means, the combination with the said parts of cooperating means to limit the said osthereby cushioning the pressure of the collector,

against the trolley wire.

ERNST A. LARSSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 7 666,660 Gabrio Jan. 29, 1901 1,088,337 Geiger Feb. 24, 1914 2,304,595 Prentice Dec. 8, 1942, 2,385,582 Larsson Sept. 25, 1945 

